[PATCH RFC V3 05/12] piix_pci: Introduces Xen specific call for irq.

[anthony.perard@citrix.com]

From: Anthony PERARD <anthony.perard@citrix.com>

This patch introduces Xen specific call in piix_pci.

The specific part for Xen is in write_config, set_irq and get_pirq.

Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
---
 hw/piix_pci.c |   10 +++++++++-
 hw/xen.h      |    6 ++++++
 xen-all.c     |   29 +++++++++++++++++++++++++++++
 xen-stub.c    |   13 +++++++++++++
 4 files changed, 57 insertions(+), 1 deletions(-)

diff --git a/hw/piix_pci.c b/hw/piix_pci.c
index f152a0f..41a342f 100644
--- a/hw/piix_pci.c
+++ b/hw/piix_pci.c
@@ -28,6 +28,7 @@
 #include "pci_host.h"
 #include "isa.h"
 #include "sysbus.h"
+#include "xen.h"
 
 /*
  * I440FX chipset data sheet.
@@ -142,6 +143,9 @@ static void i440fx_write_config(PCIDevice *dev,
 {
     PCII440FXState *d = DO_UPCAST(PCII440FXState, dev, dev);
 
+    if (xen_enabled())
+        xen_piix_pci_write_config_client(address, val, len);
+
     /* XXX: implement SMRAM.D_LOCK */
     pci_default_write_config(dev, address, val, len);
     if (ranges_overlap(address, len, I440FX_PAM, I440FX_PAM_SIZE) ||
@@ -235,7 +239,11 @@ PCIBus *i440fx_init(PCII440FXState **pi440fx_state, int *piix3_devfn, qemu_irq *
     piix3 = DO_UPCAST(PIIX3State, dev,
                       pci_create_simple_multifunction(b, -1, true, "PIIX3"));
     piix3->pic = pic;
-    pci_bus_irqs(b, piix3_set_irq, pci_slot_get_pirq, piix3, 4);
+    if (xen_enabled()) {
+        pci_bus_irqs(b, xen_piix3_set_irq, xen_pci_slot_get_pirq, piix3, 4);
+    } else {
+        pci_bus_irqs(b, piix3_set_irq, pci_slot_get_pirq, piix3, 4);
+    }
     (*pi440fx_state)->piix3 = piix3;
 
     *piix3_devfn = piix3->dev.devfn;
diff --git a/hw/xen.h b/hw/xen.h
index 14bbb6e..c5189b1 100644
--- a/hw/xen.h
+++ b/hw/xen.h
@@ -8,6 +8,8 @@
  */
 #include <inttypes.h>
 
+#include "qemu-common.h"
+
 /* xen-machine.c */
 enum xen_mode {
     XEN_EMULATE = 0,  // xen emulation, using xenner (default)
@@ -26,6 +28,10 @@ extern int xen_allowed;
 #define xen_enabled() (0)
 #endif
 
+int xen_pci_slot_get_pirq(PCIDevice *pci_dev, int irq_num);
+void xen_piix3_set_irq(void *opaque, int irq_num, int level);
+void xen_piix_pci_write_config_client(uint32_t address, uint32_t val, int len);
+
 int xen_init(int smp_cpus);
 
 #endif /* QEMU_HW_XEN_H */
diff --git a/xen-all.c b/xen-all.c
index f505563..948e439 100644
--- a/xen-all.c
+++ b/xen-all.c
@@ -8,9 +8,38 @@
 
 #include "config.h"
 
+#include "hw/pci.h"
 #include "hw/xen_common.h"
 #include "hw/xen_backend.h"
 
+/* Xen specific function for piix pci */
+
+int xen_pci_slot_get_pirq(PCIDevice *pci_dev, int irq_num)
+{
+    return irq_num + ((pci_dev->devfn >> 3) << 2);
+}
+
+void xen_piix3_set_irq(void *opaque, int irq_num, int level)
+{
+    xc_hvm_set_pci_intx_level(xen_xc, xen_domid, 0, 0, irq_num >> 2,
+                              irq_num & 3, level);
+}
+
+void xen_piix_pci_write_config_client(uint32_t address, uint32_t val, int len)
+{
+    int i;
+
+    /* Scan for updates to PCI link routes (0x60-0x63). */
+    for (i = 0; i < len; i++) {
+        uint8_t v = (val >> (8*i)) & 0xff;
+        if (v & 0x80)
+            v = 0;
+        v &= 0xf;
+        if (((address+i) >= 0x60) && ((address+i) <= 0x63))
+            xc_hvm_set_pci_link_route(xen_xc, xen_domid, address + i - 0x60, v);
+    }
+}
+
 /* Initialise Xen */
 
 int xen_init(int smp_cpus)
diff --git a/xen-stub.c b/xen-stub.c
index 0fa9c51..07e64bc 100644
--- a/xen-stub.c
+++ b/xen-stub.c
@@ -11,6 +11,19 @@
 #include "qemu-common.h"
 #include "hw/xen.h"
 
+int xen_pci_slot_get_pirq(PCIDevice *pci_dev, int irq_num)
+{
+    return -1;
+}
+
+void xen_piix3_set_irq(void *opaque, int irq_num, int level)
+{
+}
+
+void xen_piix_pci_write_config_client(uint32_t address, uint32_t val, int len)
+{
+}
+
 int xen_init(int smp_cpus)
 {
     return -ENOSYS;
-- 
1.6.5